Improvement in electro-magnetic temperature-alarms



J. H. GUEST. BLBCTROMAGNETIG TEMPERATURE ALARM. No. 79,972.

Alaze'ntd July 14, 1868.

IAT TINY UNITED STATES PATENT OFFICE.

JOHN H. GUEST, 'OE BROOKLYN, NEW YORK.

IMPROVEMENT iN ELECTRO-MAGNETIC TEMPERATURE-ALARMS.

Specilication forming part ofLettcrs Patent No. 79,972, dated July 14, 1868.

To all whom itmay concern: f

Be it known thatl, JOHN H. GUEST ofBrooklyn, in the county ot' Kings and State of New York, have invented, made, and applied to use a certain new and useful Improvement in Magnetic Alarms for Fires, 85e.; and I do hereby declare the following to be a full, clear, and exact description of the said invention, reference being had to the annexed drawings, making part of this specification, wherein- Figure 1 is an elevation of said apparatus, the bell being partially in section and one of the standards for the armature removed. Fig. 2 is a plan of themagnetic alarm with the bell partially removed 4to show the parts beneath it. Fig. 3 is an elevation of the thermometer to operate the alarm byan increase 'of the temperature, and Fig. 4 is a cross-*section of the same. l

Similar marks of reference denote the same parts. Y Heretofore the armatures of magnetic alarms have been bung on an axis and drawn back with a spring. The bearings taking the ends of said axis sometimes become' gummed up with the lubricating material, causing considerable friction, and sometimes interfering with the electricity passing through the same when the circuit is closed as the armature recedes from the magnet.

The nature of my said invention consists in a springaxis for suspending the armature, and also forming the fulcrurn for the hammer to the bell, said spring-axis throwing the armature oii' from the electro-magnet when the circuit is broken. I combine with said armature* and spring-axis an adjustable sprin g circuit-breaker that is very easily adjusted, according to the'strength of the electrical-current, soas to' make and break the circuit with precision each motionv `of the armature. A thermometer is employed to close the electrical current and cause the alarm to be sounded in cases where the thermometer rises beyond the -temperature atwhich the circuit-closer is placed.

In the drawings, a represents a stand for the magneticalarm; b b are electro-magnets; c is a bell on acolumn, d eandfarebinding-screws for the electrical'wires, all of any usual character.

g is. the armature hung from the spring-axis h, that is'fasten'ed at its ends in the standards if. Said sprin g-axis h is formed of a flat spring placed above and edgewise to the armature, so that the armature will be suspended in its position, but the spring will freelyY twist sli gh tl yI as the armature vibratcs.

The rod l, extending up from the armature, has a hammer-head or clapper at the upper end tostrike the inside of the bell when the magnetism draws the armature. It will thus be seen that the spring h becomes an axis for the armature anda fulcrum for the bell-ham' mer.

The circuit-breaker t is formed Ot' 'a spring attached at its upper end to the standard m and adjusted by the screw oat-he end oi which is formed as a button, and the neck behind this button takes aslot or mortise through the spring i.

When the apparatus is in use the electricity passes along'the wire`o, thence from the bindin g-screw f to the standard k, spring-axis h, armature g, circuit-breaker 11, standard m, th rou gh the helix of the magnet to the binding-screw c, thence to the battery, or to the apparatus that indicates the presence of undue heat, or to any other alarm.

The electro-magnet attracting the armature draws it fromthe circuitfbreaker t', and as the magnetism ceases the spring-axis h throws the armature back, closing the circuit, and so on, the Avibrations of the armature and hammer Vringing the bell.

I make use ot the thermometer o, that is formed as a bent tube attached to a wooden support, p, that hangs by angle irons l l from the ceiling near the center of the apartment, or is placed against the side wall or atimber, Or in anyplace where a changeoi` temperature would easily aec't the thermometer. q is the circuit-closing wire entering the end of said tube, and attached to the arm s, that is adjustable upon the rod t, to which one wire from the battery is connected, eitherdirectlyor after passing through the magnetic alarm, and the -other wire of the circuit passes into the mercury-bulbof the thermometer. By this construction the thermometer can be placed close up t0 the ceiling, and therefore is most easily aiected by changes of temperature, and the circuit-closer can be adjusted with great facility, so as to cause a signal by the mercury in the thermometer coming into contact with the said circuit-closer.

The circuit-closer g, arm' s, and rod t are protected .by e ease, u, that is slipped endwise upon spring-clasps 2 2, receiving the'tlanges that project inwardly from the edges of such case. l

What I claim, and desire to see-ure by Letters Patent, is-

'The spriug-axis on which the armature swings1 in combination with the hammer and bell,"as and for the purposes set forth.

2. The spring circuit-breaker i and adjusting-screw n, provided with a. head or button, in combination with the armature and spring axis h, 'for the purposes and as set forth.

J. El. GUEST.

Witnesses GEO. D. WALKEm CuAs. H. 4SMITH.

3. The alarm-thermometer, formed with the' signature the 4th day. of February, A. D. 1868. 

